dm snapshot: fix chunksize sector conversion
If a snapshot has a smaller chunksize than the page size the
conversion to pages currently returns 0 instead of 1, causing:
kernel BUG in mempool_resize.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: stable@kernel.org
diff --git a/drivers/md/dm-exception-store.c b/drivers/md/dm-exception-store.c
index 5bbce29..c7d305b 100644
--- a/drivers/md/dm-exception-store.c
+++ b/drivers/md/dm-exception-store.c
@@ -131,7 +131,7 @@
static unsigned sectors_to_pages(unsigned sectors)
{
- return sectors / (PAGE_SIZE >> 9);
+ return DIV_ROUND_UP(sectors, PAGE_SIZE >> 9);
}
static int alloc_area(struct pstore *ps)